Circuit-closer.



V. DURBIN & H. EHRISMANN.

CIRCUIT CLOSER.

APPLICATION FILED MAY 9,1913.

Patented Nov. 17, 1914.

Era-$ UNITED STATES PATENT OFFICE.

VERNON DURBIN, OF NEWTON, AND HENRY EHRISMANN, 0F BOSTEJN, MASSACHU- BETTE, ASSIGNORS TO THE H OLTZER-CABOT ELECTRIC COMPANY, OF BROOKLINE,

MASSACHUSETTS.

CIRCUIT-CLOSER.

To all whom it may concern Be it known that we, Vnaxox DURBIN and HENRY EHRISMANN, citizens ofthe United States, and residents of Newton, n the county of Middlesex, and of Boston, in the county of Suffolk, respectively, and State of Massachusetts, have invented a. new and useful Improvement in Circuit-Closers, of which the following is a specification. Our invention relates to push-button C11- cuit closers and especially to those of the self-locking type which are adapted for use in hospital signaling systems, and the object. of our invention is to improve and simplify the construction thereof 111 the manner hereinafter set forth.

One embodiment of our invention is shown in the drawings which accompany and form a part of this specification, but it will be understood that we do not llmit ourselves to the particular form shown inasmuch as various modifications may be made therein by those skilled in the art w thout departing from the spirit of our lnvention.

In the drawings,Figure 1 is an elevation of a push-button circuit-closer made in accordance with' the present invention, the casing being shown in section. Fig. 2 is a central vertical section taken on the line 22 of Fig. 5. Fig. 3 is a central vertical section taken on the line 3-3 of Fig. 5. Fig. a} is an elevation with the easing shown in section illustrating the manner of unlocking the circuit-closer by akey. Fig. 5 is a plan view with the casing removed.

In the particular drawings selected for more fully disclosing our invention, 1 represents a casing of insulating material such as vulcanite, arranged to receive at its lower end a plug 2, secured thereto by screws which pass through holes in the casing and corresponding holes, one of which is shown at 3 in the stem 4 which is formed integral with the plug and which carries the springfinger circuit-closing elements.

In the present instance three spring-fingers 5 of copper are shown, each secured in one of the grooves 17 of the stem by means ofscrews, and each provided with a backing plate 5 of brass. lVe prefer to employ a fourth spring-finger 6 which, being slightly shorter than the fingers 5, terminates Specification of Letters Patent.

Application filed May 9, 1913.

Patented Nov. 17, 1914. Serial No. 766,539.

below the ends thereof plate 6'.

Secured to the stem at diametrically opposite points are two latching members 7 of suitable spring material, the upper ends of which are suitably shaped to limit the upper movement of the circuit-closer and also to hold the same in circuit-closing position.

A pin 9 is suitably attached to the pushbutton 10 and resilient means such as the spiral spring 9 surrounding said pin and having its ends in recesses in the push-button and stem respectively serves to maintain the circuit-closer normally in circuit-opening position.

The lower portion of the push-button consists of a polyangular member 12 of insulating material, herein shown as having four sides, and the contact-maker 11 of brass or other conducting material is supported on the portion 12 of the push-button. The contactmaker is shown in the present instance as a squared brass plate having its corners cut away for the purpose of permitting the down turned ends of the latching members to come in contact with opposite corners of the squared member 12, as shown in Figs. 1 and ,5.

Surrounding the push-button and arranged within the bushing 14 of the casing is a collar 13 having a cone-shaped lower portion.

For the purpose of guiding the push-button, a pin 16 depending from the member 12 and taking into a hole in the stem 4 may be employed. Suitable conductors 8 passing through a hole in the plug and branching perforations communicating therewith are attached as by screws to'the four circuitclosing spring-fingers.

In its normal position the contact-maker is out of electrical connection with the spring-fingers, and the latching members, against the ends of which the spring 9 forces the squared portion 12 of the pushbutton, hold the latter and its attached contact-maker in the position shown in Fig. 1.

When the push-button is depressed, the spring-fingers 5 make electrical contact with the contact-maker and the ends of the latching members spring inwardly, so that when and has a backing the pressure .on the push-button is released,

they serve to hold the contact-maker in cirpression of the push-button will, without moving the contact-maker 11 out of engagement with the fingers 5, bring the springfinger 6 also into electrical connection with said contact-maker and will closethe circuit ofa buzzer or other audible signaling device. This is accomplished in the present,

instance by making the interval between the upper end of the spring-finger or circuitclosing element 6 and the upper ends of the spring-fingers 5 shorter than the length oi the contact-maker 11, as clearly shown in Fig. i. 'When this pressure is released, the parts again take the position shown in Fig. 3. When the call has been answered, the push-button is unlocked by means of a key or other suitable implement, such as that shown at 15, which fits over the upper end of the push-button and forces the collar 13 downwardly, so that its flarin end spreads the latching members 7 as shown in Fig. 4:. It will be obvious that when the key is removed, the contact-maker will slide past the latches on the latching members and the ends of the latter will again come in contact with the corners of the squared member 12.

as shown in Fig. 1, thereby holding the parts in circuit-opening position.

We claim:

1. A push -button circuit closer comprising in combination a tubular casing, a longitudinally-bored stem secured within said casing, circuit-closing spring-fingers carried by sald stem, a pin having its lower portlon arranged within the bore of said stem, a push-button secured to the upper portion of said pin and extending beyond said casing, acontact-Inaker carried by said push-button, resilient means for normally maintaining said contact-maker out of contact with said spring-fingers, latching members for holding said contact-malrer in circuit-closing position, and key-controlled means cooperating with said latching members for releasing said contact-maker from such circuit-closing position.

2. A push button circuit closer compris ing in combination a casing, a stem secured within said casing, circuit-closing springfingers carried by said stem, a pin movable with respect to said stem, a push-button secured to the upper portion of said pin, a contact-maker carried by said push-button, resilient means for normally maintaining said contact-maker in circuit-opening position, latching members for holding said contact-maker in circuit-closing position, and

key-controlled means coiiperating with resilient means latching means for releasing said contactmaker from said circuit-closing position.

3. A push button circuit closer comprising in combination a tubular casing, a longitudinally bored stem secured within said casing, circuit-closing spring-fingers carried by said stem, a pin having its lower portion arranged within the bore of said stem, a push-button secured to the upper portion of said pin and extending beyond said casing, a contact-maker carried by said push-button, for normally maintaining saidcontact-maker out of contact with said spring-fingers, latching members for holding-said contact-maker in circuit-closing position with respect to said spring-fingers,

and a circuit-chrsing element out oielectrioal connection with said contact maker when the latter is held by said latching members in said circuit-closing position, said circuitclosing element terminating below the upper ends of said spring-fingers and cooperating with said contact-maker upon further de-' pression of the latter.

a. A push-button circuit-closer comprising in combination, a tubular casing, a longitudinally-bored stem secured within said casing, circuit-closing spring-fingers carried by said stem, a pin having its lower portion arranged within the bore of said stem, a

push-button secured to the upper portion of said pin and extending beyond said casing, a contact-maker carried by said pushbutton, resilient means for normally maintalmng said contact-maker out of contact with said spring-fingers, latching members for holding said contact rnairer in circuitclosing pos1t1on with respect to said springfingers, a circn1t-closing element out of electrlcal connection with sand contact-maker when the latter is held by said latching members in said circuit-closing position, the said circuitclosing element terminating be low the upper ends of said spring-fingers and cooperating with said contact-maker upon further depression of the latter, and key-controlled means for releasing said contact-maker from said circuit-closing posi tion.

5. A push-button circuit-closer comprising in combination'a'oasing, a stem secured within said casing, circu1t-closing spring-- lingers car ied by said stem, a pin movable with respect to said stem, a push-button secured to the upper portion of said pin, a contact-maker carried by said push-button, resilient means for normally maintaining said. contact-maker in circuit-opening post.

tion, latching members for holding said contact-maker in circuit-closing position with respect to said spring-closing fingers, and a circuit-closing element terminating below the upper ends of said sprin -fingers. the interva between the upper ct said air cuitclosing element and upper a ct said spring-fingers being shorter than the length of said contact-maker.

6. A push-button circuit-closer comprising in combination a casing, a stem secured within said casing, circuit-closing springfingers carried by said stem, a pin movable with respect to said stem, a push button secured to the upper portion of said pin, a contact-maker carried by said push-button, resilient means for normally maintaining said contact-maker in circuit-opening position, latching members for holding said contact-maker in circuit-closing position with respect to said spring-closing fingers, a circuit-closing element terminating below the upper ends of said spring-fingers, the interval between the upper end of said circuitclosing element and the upper ends of said spring-fingers being shorter than the length of said contact-maker, and key-controlled means for releasing said contact-maker from said circuit-closing position.

7 A push-button circuit-closer comprising in combination a casing, circuit-closing spring-fingers located inside said casing, a push-button, a contact-maker operated by said push-button, means for normally maintaining said contact-maker in circuit-opening position, latching members for holding said contact-maker in circuit-closing position with respect to said circuit-closing spring-fingers, and a circuit-closing element terminating below the upper ends of said spring-fingers and cooperating with said contact-maker pon further depression of the latter, the interval between the upper ends of said circuit-closing element and the upper ends of said spring-fingers being shorter than the length of said contactmaker.

8. A push-button circuit-closer comprising in combination a casing, circuit-closing sprin -fingers located inside said casing, a pushutton, a contact-maker operated by said push-button, means for normally maintaining said contact-maker in circuit-opening position, latching members for holding said contact-maker in circuit-closing position with respect to said circuit-closing spring-fingers, a circuit-closing element terminating below the upper ends of said spring-fingers, and cooperating with said contact-maker upon further depression of the latter, and key-controlled means for releasing said oontact-maker from said circuit-closing position.

In testimony whereof, we have hereunto subscribed our names this 8th day of May,

VERNON DURBIN. HENRY EHRISMANN. l/Vitnesses:

Gno. K. WOODWORTH, E. B. TOMLINSON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

